This invention relates to a syringe and in particular to a syringe having an integral retractable sheath.
Syringes are used for injections, obtaining fluid samples and general laboratory utilization. Generally, as manufactured, syringes are packed with a disposable, removable sheath. Once the sheath is removed from the needle it may be discarded or lost such that the needle remains exposed. The syringe, if a plastic body, is generally discarded following use. If a glass body, the syringe may sometimes be sterilized and reused. In either case, following use, the needle may be recapped which leads to the dangers of self-inflicted needle sticks.
While disposal would appear to be straightforward, a number of problems occur. Most common is that the exposed and contaminated needle not infrequently scratches or wounds some member of the health care team, e.g., physicians, nurses or those individuals handling trash. For this reason a myriad of devices such as "needle boxes" and the like have evolved to safely dispose of syringes and/or needles. The use of those devices is often inconvenient and expensive such that in many facilities they are ignored or nonexistent.
Even when conveniently located in the patient's room or near the application site, many professionals have been trained to recap the needle with the removable sheath to prevent inadvertent needle sticks. Some health care professionals also recap needles to protect themselves. Additionally, they snap off the needle to prevent reuse by drug abusers who might avail themselves of this supply.
The need to protect individuals from any inadvertent contact from needles has become increasingly important with the many diseases (e.g., hepatitis, aids, etc.) that can be transmitted in this manner. The trend to return patients to their home environment as soon as possible has also increased the possibility that a friend or family member might also be at risk for exposure to a contaminated needle.
In the case of syringes that are to be reused, a requirement exists to sheath the needle when the device is being processed for reuse. If the original sheath is discarded a new one must be obtained. The requirement for maintaining a separate inventory of components makes the reuse of syringes expensive and time consuming.